Hi Henning! It's a real (Tomcat) cluster. Two instances of Tomcat talking to a single database. (no database replication). I use Apache/mod_jk to split requests (based on session) between the two Tomcats. Allows me to run high number of users with a memory-heavy application.
Thought briefly about database replication but since this is write-heavy application it didn't seem to make sense. thanks, WILL On 12/5/06, Henning P. Schmiedehausen <[EMAIL PROTECTED]> wrote:
"Will Glass-Husain" <[EMAIL PROTECTED]> writes: >Hi, >I just set up a new 2 server cluster with two instances of Tomcat both >reading/writing from a single database. I'm using Torque 3.0, the >default ID Broker and MySQL 5. (InnoDB) Real cluster or just master/slave (or master/master with only one master active at a time)? The latter is just replication, not a real cluster. >My problem... Under heavy load, I notice that most write requests on >one of the servers fails with a duplicate ID error. Typically, each >page request that fails does 10-20 insert statements. >Any tips as to how I might make this cluster work with simultaneous writes? a) in a master/master config, you can not write to both masters at the same time. End of story. I had a summer project where we tested exactly that *very* extensively. It does not work. No matter what you google on the internet or what mysql.com wants to tell you. You will get the described error sooner or later. If you want to have master/master with failover, that is fine. Two active masters not. b) you probably run into the AUTO_INCREMENT problem. Make sure that you have 5.0.20 at least. See http://dev.mysql.com/doc/refman/5.0/en/replication-features.html for some docs. Best regards Henning -- Henning P. Schmiedehausen -- [EMAIL PROTECTED] | J2EE, Linux, 91054 Buckenhof, Germany -- +49 9131 506540 | Apache person Open Source Consulting, Development, Design | Velocity - Turbine guy "Save the cheerleader. Save the world." --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
-- Forio Business Simulations Will Glass-Husain [EMAIL PROTECTED] www.forio.com --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
